1. Field of the Invention
The present invention relates to a resealable closure mechanism, such as may be used on a thermoplastic pouch.
2. Description of the Background of the Invention
Thermoplastic pouches having one or more resealable closure mechanisms extending along an opening into an interior thereof are often used to store perishable contents, such as food. In order to keep the food stored inside the pouch fresh for an extended period, a user may expel excess air out of the pouch before completely sealing the closure mechanism. Some pouches allow a vacuum to be formed inside the pouch and then be sealed so as to vacuum pack the contents of the pouch. Other pouches have been developed that have a separate air evacuation route so that air may be removed from the pouch after the closure mechanism has already been sealed. Sometimes, a resealable closure mechanism is included that has specialized features for providing beneficial sealing characteristics beyond simple interlockability.
For example, one closure mechanism has a male and female closure element attached to inner surfaces of opposing pouch sidewalls, respectively. A frangible diaphragm extends across an opening of the female closure element to prevent complete engagement of the closure elements during manufacture, handling, and stacking.
Another closure mechanism has a gasket flange loosely disposed between opposing first and second closure elements attached to opposing first and second sidewalls, respectively, of a pouch. The gasket flange is attached to one or both of the first and second sidewalls of the pouch on the interior and/or exterior of the profiles and the gasket flange extends into an interior of the pouch. The profiles are interlocked with the gasket flange interposed therebetween to improve the efficacy of the seal therealong.
Yet another closure mechanism has a female profile having a base with a first pouch sidewall extending therefrom. Apertures through the base of the female profile provide communication between a space between first and second female legs that extend from the base and an opposite side of the base so that a male profile inserted into the female profile will urge any particles lodged in the space to pass through the apertures and out of the closure mechanism.
A further closure mechanism has first and second profiles that interlock in a closed state to form a space therebetween extending longitudinally along the length of the zipper. The bases of both zipper profiles are provided with apertures for enabling particulate matter trapped in the space between the profiles to pass through the apertures into the interior volume of the package.